<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item v-for="(item,index) in levelList" :key="item.path">
        <span
          v-if="item.redirect === 'noRedirect' || (index == levelList.length - 1 && levelList.length > 1)"
          class="no-redirect"
        >
          {{ item.meta.title }}
        </span>
        <a v-else @click.prevent="handleLink(item)" class="title">{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
export default {
  name: "breadcrumb",
  data() {
    return {
      levelList: null
    }
  },
  watch: {
    $route(route) {
      // if you go to the redirect page, do not update the breadcrumbs
      if (route.path.startsWith('/redirect/')) {
        return
      }
      this.getBreadcrumb()
    }
  },
  created() {
    this.getBreadcrumb()
  },
  methods: {
    getBreadcrumb() {
      // only show routes with meta.title
      let matched = this.$route.matched.filter(item => item.meta && item.meta.title);

      this.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false);
    },
    handleLink(item) {
      const { redirect, path } = item
      if (redirect) {
        this.$router.push(redirect)
        return
      }
      this.$router.push(path)
    }
  }
}
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
  display: inline-block;
  font-size: 14px;
  line-height: 50px;
  margin-left: 20px;

  .no-redirect {
    color: #97a8be;
    cursor: text;
  }
  .title {
    color: #1F2733;
    font-size: 14px;
    line-height: 20px;
    font-family: 思源黑体;
  }
}
</style>
